Teeth names are created by a combination of 4 different characteristics: 1  The jaw where they are located: upper and lower (alternatively the terms maxillary and mandibular can be used) 2  The side of the face: left and right.  The type of tooth: incisor, canine, premolar, and molar.
Vampire bats are members of the New World Leaf-nosed bats, the Phyllostomidae. All three species of living vampire bats occur in South and Central America. Fossils of three other species reveal that several thousand years ago vampire bats were more widespread.
The vampire bat lineage diverged from its family 26 million years ago. The hairy-legged vampire bat likely diverged from the other two species of vampire bats 21.7 million years ago. Because the hairy-legged vampire bat feeds on bird blood and it is the ancestral vampire bat, it is likely that all vampire bats initially fed on bird blood.